Ahmad Shanei - Medical Physics Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
Ameneh Sazgarnia - Medical Physics research Center, Mashhad University of Medical Sciences, Mashhad, Iran|Department of Medical Physics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

Acoustic cavitation which occurs at high intensities of ultrasound waves can be fatal for tumor cells. The existence of dissolved gases and also the presence of nanoparticles (NPs) in a liquid, irradiated by ultrasound, decrease the acoustic cavitation onset threshold and the resulting bubbles collapse. On the other hand, due to unique capabilities and optical properties of gold nanoparticles (GNPs), they have been emphasized as effective NPs in the field of tumor therapy. Absorption of the laser light by GNPs causes the water molecules around the NPs to evaporate and produces vapor cavities. In this paper, we have reviewed published studies in the fields of ultrasound therapy, sonodynamic therapy (SDT) and synergism of low-level ultrasound and also laser radiation in the presence of GNPs.

Cavitation, Gold Nanoparticle, High Intensity Focused Ultrasound, Laser excitation, Sonodynamic therapy, Therapeutic ultrasound